| Angiotensin-converting enzyme of the human small intestine. Subunit and quaternary structure, biosynthesis and membrane association. | |
| | |
MedLine Citation:
|
PMID: 1326943 Owner: NLM Status: MEDLINE |
Abstract/OtherAbstract:
|
Angiotensin-converting enzyme (ACE) was isolated from detergent-derived extracts of human intestinal brush-border membranes (BBMs) by immunoprecipitation using a monoclonal antibody. Analysis of the immunoprecipitates by SDS/PAGE revealed a polypeptide of apparent M(r) 184,000 under reducing and non-reducing conditions, indicating that ACE does not contain intermolecular disulphide bridges. The quaternary structure of ACE was examined using cross-linking experiments with dithiobis[succinimidylpropionate] (DSP) and density gradient centrifugation on sucrose gradients. Both approaches demonstrated that ACE is assembled in the membrane as a monomer. By contrast, the control glycoprotein aminopeptidase N (ApN) exists as a dimer. Biosynthetic labelling experiments in intestinal tissue explants demonstrated that the 184,000-M(r) protein is generated from a single-polypeptide, mannose-rich precursor of ACE (M(r) 175,000) by modification of the carbohydrate side-chains in the Golgi apparatus. The mode of association of the mature form of the enzyme with BBMs was investigated by hydrophobic labelling of right-side-out brush-border vesicles with the photoactivatable carbene-generating reagent 125I-labelled 3-(trifluoromethyl)-3-(m[formylamino]phenyl)diazirine (125I-labelled TID), followed by treatment with trypsin at dilutions that do not cause substantial degradation of ACE. These studies demonstrated that ACE is associated with the membrane via a hydrophobic segment. Furthermore, treatment of 35S-labelled inside-out membrane vesicles with trypsin revealed that ACE possesses a cytoplasmic tail, and therefore has a transmembraneous orientation. |
| | |
Authors:
|
H Y Naim |
Related Documents
:
|
1901633 - Variable distribution, in four rat brain areas, of the three natural forms of peptide h... 22835833 - Development and application of a method for identification of isothiocyanate-targeted m... 7886453 - Epithelial antibiotics induced at sites of inflammation. |
Publication Detail:
|
Type: Journal Article; Research Support, Non-U.S. Gov't |
Journal Detail:
|
Title: The Biochemical journal Volume: 286 ( Pt 2) ISSN: 0264-6021 ISO Abbreviation: Biochem. J. Publication Date: 1992 Sep |
Date Detail:
|
Created Date: 1992-10-19 Completed Date: 1992-10-19 Revised Date: 2013-03-26 |
Medline Journal Info:
|
Nlm Unique ID: 2984726R Medline TA: Biochem J Country: ENGLAND |
Other Details:
|
Languages: eng Pagination: 451-7 Citation Subset: IM |
Affiliation:
|
Institute of Microbiology, Heinrich-Heine University of Düsseldorf, Germany. |
Export Citation:
|
APA/MLA Format Download EndNote Download BibTex |
| MeSH Terms | |
Descriptor/Qualifier:
|
Cell Membrane
/
enzymology Cross-Linking Reagents Electrophoresis, Polyacrylamide Gel Humans Intestine, Small / enzymology* Macromolecular Substances Microvilli / enzymology Organ Culture Techniques Peptidyl-Dipeptidase A / chemistry, metabolism*, secretion Precipitin Tests Protein Conformation Succinimides / chemistry |
| Chemical | |
Reg. No./Substance:
|
0/Cross-Linking Reagents; 0/Macromolecular Substances; 0/Succinimides; 57757-57-0/dithiobis(succinimidylpropionate); EC 3.4.15.1/Peptidyl-Dipeptidase A |
| Comments/Corrections | |
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine
Previous Document: Characterization of a Zn(2+)-requiring glycerophosphocholine cholinephosphodiesterase possessing p-n...
Next Document: Accumulation of PtdIns(3,4)P2 and PtdIns(3,4,5)P3 in thrombin-stimulated platelets. Different sensit...